Log barking machine having bilateral cutters, brushes, and feed rollers



Feb. 5, 1957 Filed Oct. 16, 1955 J. L. GYLLENBERG LOG BARKING MACHINEHAVING BILATERAL CUTTERS, BRUSHES AND FEED ROLLERS 11 Sheets-Sheet 2JNVENTOR.

JOHN L. an LE/VBERG BY ATTORNEYS J. L. GYLLENBERG LOG BARKIN Feb. 5,1957 2,780,252

G MACHINE HAVING BILA'IERAL CUTTERS, BRUSHES AND FEED ROLLERS llSheets-Sheet 3 Filed Oct. 16, 1953 k mww mww mww mww ww mww mmm 8 RM RM35 mm. A \A/ A Q Rm I 11111 3m 11111111 INVENTOR.

JOHN LGYLLE/VBERG Feb. 5, 1957 J. YLLENBERG 2,780,252 LOG BARKIN HINEHAVING BILATER CUTTER-S, B. SHES AND FEED ROLLER Filed Oct. 16, 1953 11Sheets-Sheet 4 M INVENTOR. N JOH/V LGYLLEA/BERG W W W ATTORNEYS Feb. 5,1957 J. L. GYLLENBERG LOG BARKING MACHINE HAVING BILATERAL CUTTERS,BRUSHES AND FEED ROLLERS ll Sheets-Sheet 5 Filed Oct. 16, 1953 INVENTOR.JOHN L. a YLLE/VBE/FG ATTORNEYS Feb. 5, 1957 J. L. GYLLENBERG 2,780,252

LOG BARKING MACHINE HAVING BILATERAL. CUTTERS, BRUSHES AND FEED ROLLERSll Sheets$heet 6 Filed 001;. 16, 1953 v INVENTOR. ao/m/ L. GYLLE/VBERG WATTORNEYS Feb. 5, 1957 J. GYLLENBERG 2,780,252

LOG BARKING MACHINE HAVING BILATERAL CUTTER-S, BRUSHES AND FEED ROLLERSFiled Oct. 16,1955 11 Sheets-Sheet 7 m2 \mw R GE 5 T Y NN F. F. N V H mmm 7 an L M M m nvw 5 72mm mEw mm; mmww ma .mnmm

Feb. 5, 1957 J. GYLLENBERG 2,780,252 LOG BARKING MACHINE HAVINGBILATERAL CUTTERS, BRUSHES AND FEED ROLLERS 11 Sheets-Sheet 8 Filed001;. 16, 1953 INVENTOR. JOHN L. GYLLE/VQERG BY ATTORNEYS Feb. 5, 1957J. L. YLLENBERG 2,780,252

LOG BARK]: G MACHINE HAVING BILATERAL CUTTERS, .USHES AND FEED ROLLERSFiled Oct. 16, 1953 ll Sheets-Sheet 10 JOHN L. GYLLE/VBERG W M]ATTORNEYS Feb. 5, 1957 J. GYLLENBERG 2,780,252 LOG BARKING MACHINEHAVING BILATERAL CUTTERS, BRUSHES AND FEED ROLLERS Filed Oct. 16, 1953ll Sheets-Sheet 11 557 563 f 505- 597 50/ 555 599 l 7 I 495 57/ I 58 Q573' 577 595 INVENTOR. JOHN L. an LE/VBERG BY ATTORNEYS United StatesPatent LOG BARKING MACHINE HAVING BILATERAL cnrrnns, BRUSHES, AND FEEDnoLLERs John L. Gyllenberg, Baker, Oreg., assigncr to AnthonyBrandenthaler, Baker, Greg.

Application October 16, 1953, Serial No. 386,491 11 Claims. (Cl. 144-208) This invention relates to a machine for removing bark from logs,such machines being referred to as log-barking machine's.

There has long existed a pressing demand for a machine capable ofquickly and eifectively removing the bark and underlying cambium' layerfrom logs, as is evidenced by the numerous patents granted on suchmachines. A successful hydraulic log-barking machine has been developedcomparatively recently, but thism-ac-hine is very expensive and thus isavailable to only a small segment of the lumber industry. Mechanicallog-barking machines are, in general, much less expensive than hydraulicmachines, but, although hundreds of patents have been granted on suchmachines, it is well known in the trade that they have not provedsuccessful, and none have been adopted by even a small segment of theindustry.

Various reasons are attributed to these failures. A primary reason hasbeen the inability of the machines to entirely remove the cambium layerfrom even straight logs, and if such material is not entirely removed,the slabs, edgings, et cetera, formed when the logs are cut into lumber,are not satisfactory for use in paper manufacture, which is a primarysource of the demandfor log-barking machines. Another important reasonwhy prior mechanical log-barking machines have been failures is that,while some of them do a creditable job of removing a substantial portionof the bark and cambium from straight, cylindrical logs having fewer noknots, branch stubs, and the like, which logs form only a smallpercentage of those handled at a mill, they have been incapable ofhandling bowed, crooked, and otherwise unsymmetrical l-ogs, or logs withmany knots and branch stubs. There are other reasons for the failureofprior mechanical log-barking machines, but the fact that none of themhave been adopted by even a small segment of the industry showsconclusively that they have not been successful.

It is a main object of the present invention to provide a mechanicallog-barking machine which costs only a fraction of the price of ahydraulic machine, and which is completely successful in removing notonly the bark but also the underlying cambium layer from all logssuitable for sawmill work, including logs which are bowed and crooked,and those which are covered with knots and branch stubs.

The concepts of the present invention are embodied in a mechanicallog-barking machine having, broadly speaking, toothed bark-removingmeans arranged to engage the surface of a log and to remove a largepercentage of the bark, and to score, tear and remove at least some ofthe cambium layer, in combination with wirebrush means operable to workon the thus prepared log surface to entirely remove the little bark leftthereon and entirely remove the cambium layer, such operations beingcarried out without any substantial damage to the useful wood fibers ofthe log; i

As previously mentioned, prior mechanical log-barkice ing machines havebeen unable to handle logs having knots and branch stubs, primarilybecause the bark-re moving means simply rode over the knots and stubsand thus could not engage the bark immediatelysurrounding such knots andstubs.

The concepts of the present invention are more specifically embodied ina machine wherein the toothed barkremoving means is designed to swivelor turn upon engagement with a knot or stub and so to bring at least aportion of such toothed means int-o engagement with, and remove the barkfrom, the area immediately surrounding knots and branch stubs, andwherein the wirebrush means is formed or provided with a recess toenable it to efiectively enclose and surround a knot or branch stub andremove the bark portions remaining thereon and therearound, and toentirely remove the cambium layer in such areas.

It i another object of the present invention to provide a log-barkingmachine having a novel log-rotating-andfeeding arrangement, and, inparticular, comprising two elongated, extensible, articulatedlog-feeding members spaced to cradle a log therebetween, ingincorporated therein spaced, toothed, log-feeding elements, there beingmeans for rotating the members whereby the elements rotate a log, andmeans for disposing the axe of rotation of the elements angularly to thedirection of extension of the members whereby the elements feed the loglongitudinally along at a speed proportional to the magnitude of theangle of departure of said axes from said direction.

A further object of the present invention is to provide an arrangementof the type described immediately above, wherein there is a mechanismfor moving feeding members toward and away from one another alonginclined planes to provide a log-receiving cradle adapted to accommodatedififeren t-diameter logs, and whereby logs of different diameters maybe fed into the cradle from a fixed-level log-input-feeding means.

A still further object of the present invention is to provide, in alog-barking machine having two log-rotating-and-feeding membersadjustable toward or away from one another to vary the cradle providedthereby, log hold-down means arranged to engage the top of a log andhold the log down on the feeding members, the hold-down means beingoperatively connected to the feeding members to be movable, in responseto a change in spacing between the members, to a position outwardly fromits initial position, when the spacing be tween the members isincreased, and inwardly from its initial position, when the spacingbetween the members is decreased, whereby the hold-down means is adaptedto elfectively engage and hold down log of different sizes.

Further objects of the present invention are to provide a novel controlsystem for controlling the sizeof the cradle provided by feeding membersof the type described above, and for controlling the angular dispositionof the axes of rotation of the toothed feeding element-s, incorporatedin such feeding members, relative to the direction of extension of suchmembers.

. Various other objects of the present invention will be apparent fromthe following description taken in connection with the accompanyingdrawings wherein:

Fig. l' is a side view of a log-barking machine embodying the conceptsof the present invention, showing a log of considerable size beingoperated on by the machine;

Fig. 2 is a plan view of the machine disclosed in Fig. 1;

Fig. 3 is an end view taken in the direction of the arrows 3-3 in Fig.2; i

Fig. 4 is a fragmentary, line 4-4 of Fig. 3, showing log-feedingelement;

Fig. 5 is a fragmentary, sectional view taken along line the manner ofsupporting a said members havsectional view taken along -5 of Fig. 3,showing the cleaning fork for a feeding element;

Fig. 6 (Sheet No. 1) is a view in plan showing one row of log-feedingelements and the connections between said elements, the full linesshowing the feeding elements in their neutral positions and the dottedlines showing the elements in positions for feeding a log forwardlythrough the machine,

Fig. 7 (Sheet No. 5) is an enlarged plan view of the feeding-elementanglecontrol box located in the control booth, parts being broken awayfor convenience in illustration;

Fig. 8 is a front view of the control box disclosed in Fig. 7, taken inthe direction of the arrows 83 in Fig. 7, parts being broken away forconvenience in illustration;

Fig. 9 (Sheet No. 6) is a schematic diagram of the feeding-elementangle-control system;

Fig. 10 (Sheet No. 4) is a sectional view taken along line 10-10 of Fig.2, showing part of the mechanism for changing the size of the cradle fora log;

Fig. 11 (Sheet No. 6) is a schematic diagram showing the manner ofoperation of the cradle-control system;

Fig. 12 (Sheet No. 7) is a front elevation of the control box for thecradle-control system for the various bark-removing instrumentalities,and for the log holddown devices, parts being broken away forconvenience in illustration;

Fig. 13 is a sectional view taken along line 1313 of Fig. 12;

Fig. 14 is a sectional view taken along line 1414 of Fig. 13, showingpart of the cradle-control system;

Fig. 15 (Sheet No. 8) is a sectional view taken along line 15-15 of Fig.13;

Fig. 16 is a fragmentary, perspective view showing the relation of theswitch rollers to the two strip cams of the log-cradle-control system;

Fig. 17 (Sheet No. 9) is a sectional view taken along line 17-17 of Fig.2, showing the construction of one of the first pair ofbark-cutting-and-removing instrumentalities and one of the second pairof bark-cutting-andremoving instrumentalities;

Fig. 18 (Sheet No. 10) is a view taken in the direction of the arrows18--18 in Fig. 3, showing the manner of mounting a hold-down roller;

Fig. 19 (Sheet No. 9) is a view taken along line 19-19 of Fig. 17;

Fig. 20 (Sheet No. 5) is an enlarged view taken along line 20-40 of Fig.17, showing more fully the construction of one of the secondbark-cutting-and-removing instrumentalities;

Fig. 21 is a side view taken from the right of the cutting devicedisclosed in Fig. 20;

Fig. 22 (Sheet No. 11) is a fragmentary, sectional view taken along line22-22 of Fig. 21, showing the manner of eccentrically mounting a cutter;

Fig. 23 is a view taken along line 2323 of Fig. 21, more fully showingthe construction of the equalizer bar;

Fig. 24 (Sheet No. 10) is a sectional view taken along line 2424 of Fig.2, showing the construction of the wire-brush units;

Fig. 25 (Sheet No. 8) is a view looking at the operating face of a wirebrush;

Fig. 26 is a sectional view through the wire brush showing the manner ofits operation on a knot; and

Fig. 27 (Sheet No. 11) is a schematic view showing the manner ofcontrolling and operating a wire-brush unit.

Referring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, there is disclosed alog-barking machine embodying the concepts of the present invention, andin which a log of considerable size is shown being processed. Themachine comprises a frame including five upright, M- shaped, alignedframe sections 11, 13, 15, 17 and 19 spaced from one another as shown inFigs. 1 and 2, and

adapted to be directly or indirectly fixed to the iloor of a building orother suitable structure. Each frame section comprises two spacedM-shaped members fixedly connected at their lower ends by base plates20, and at the upper side portions thereof by side plates, relativelynarrow side plates 21 being provided for the sections 11 and 19, andrelatively deep side plates 22 being provided for the remaining sections(see Fig. 1).

Two spaced rows of log-rotating elements Provided along each inclined,upwardly facing surface of each M-shaped member is a guide 23 (see Fig.4), the guides on opposed frame members facing one another and slidablyreceiving a feed-element-supporting plate 25 of generally rectangularconfiguration (compare Figs. 2, 4 and 10). Each plate 25 is adjustablyheld in a selected position along the guides 23 in a manner to bepresently set forth. Upon each feed-elementsupporting plate 25 ispivotally mounted at 26, for swiveling movement about an axisperpendicular to said plate, a feed-element pivot plate 27 of generallypear-shaped configuration, as shown in Figs. 2 and 6.

A toothed feed element 23, having conico-frustum ends and two annulargrooves 35 therearound, is provided for each pivot plate 27, and has ashaft 31 journaled in uprights 32 (see Fig. 4) fixed to said pivotplate. A cleaning fork 33 (see Fig. 5) is provided for each feed element29, and is supported by arms 34 forming extensions of the associateduprights 32, and fits within the upper portions of the annular groovesof the feed element to automatically clean the element as the element isrotated by means to be presently set forth. As is apparent from thearrows in Fig. 3, the feed elements 29 on each frame section rotate inthe same direction, counterclockwise as shown, and so the arms 34 ofboth pairs of the uprights 32 on each frame section extend to the left,as the parts are depicted in Fig. 3, to dispose each fork 33 to the leftof its feed element in position so that the prongs thereof elfectivelyclean the feed element.

There is a curved log-retaining arm associated with each feed element,the left-hand retaining arm in Fig. 3 being given the reference numeral35 and being secured to the nearest arm 34 shown (compare Figs. 3 and5), whereas the right-hand retaining arm is given the reference numeral36 and is secured to the right edge of the nearest upright 32.

As is apparent from Figs. 2 and 3, the feed elements 29 are arranged intwo longitudinal rows to provide a cradle for a log labeled A, theelements being operable when rotated to rotate the log and, whenarranged with their axes of rotation other than parallel to thedirection of extension of said rows, to feed the log one way or theother along the machine, depending on which direction they are swiveledfrom their parallel positions.

Simultaneous articulation of all log-rotating elements to cause feedingof a log Each row of the feed elements 29 is connected in endto-endfashion in a manner to provide an elongated, extensible, articulatedfeed member. Figs. 2 and 6 best show this arrangement, and thearrangement will be described in connection with the top row of elementsas the parts are depicted in Fig. 2. Connected to the opposite ends ofeach feed element shaft 31, except for the lefthand end of the leftmostshaft in Fig. 2, is a universal joint 41, and connecting the universaljoints of the various feed elements of the row are two-part,spline-connected, telescopic shafts. The three centrally locatedfeedelement shafts 31 are connected by relatively short twopart shafts43, whereas there is a relatively long two-part shaft 45 connecting theshaft 31 of each end feed element with the shaft 31 of the adjacent feedelement. A twopart, spline-connected, telescopic input shaft 47 (seeFig. 2) is connected and transmits power to the right-hand WZQQQQZuniversal jo n hwisheli ad mdn th h ft 3 9 the rightmost feed element ofthe ow.

The opposite row 1 of 1 feedelement shafts are similarly connected anddriven. By: such an arrangement, the feed elements of a row are drivenat the same speed in the same direction. The two input shafts 47 arearranged to drive the two rows of feed elements in; the same direction,as is apparent from the direction-ofrrotation arrows in Fig. 3.

When the feed elements are swiveled on their supporting plates by meansto be presently described, the distances between the adjacent .ends ofthe feed-element shafts varies, the two-part shafts-varying in length toaccommodatesuch action. The dottedline position of the parts in Fig. 6shows this action.

The mechanism for. controlling the angular disposition of the axes ofrotationv of the feed elements will now he described. Referringparticularly to Fig. 6, the pivot plates27 of each row of feedelements29 are'pivotally connected at the protruding portions thereof at 69 to acontrol link 71 extending longitudinally of the machine. The right-handend of each link, as the partsare depicted in Figs. 2 and 9, is bentoutwardly and is pivotally connected to a sliding block 73 which isslidably received Within the elongated slot of a slotted link 75. Theslotted link for the upper row of feed elements, as the partsaredepicted in Figs. 2 and 9, is pivoted at its upper end to one end of alink 77, the latter being pivoted at 79 to the frame section 19.

A response cable 81 is connected at one end to the slotted link 75 andis trained about a sheave 83 rotatably mounted on the frame section 17.(see Figs. 2 and 9), and then about a sheave 85 mounted on a controlbooth generally indicated at 87. The cable is then connected at itsother end to a response lever. 89 (compare Figs. 2, 7

and 9) which forms part of a control box generally indicated at 9%,about which more will be presently said.

The other end of the upper slotted link 75 (Fig. 2) is pivoted to twoplain links 91 and 93, the former being pivoted to the frame section 19and the latter being pivoted to an actuating disk 95. It is apparentthat the link 77 and the link 91 provide a parallel linkage arrangementfor the associated link 75, so that the slot of said link will always bemaintained normal to the longitudinal axis of themachine. The disk 95 ispivotally mounted at 96 on a bracket 97 fixed to the frame section 19,and has an arm 99 pivotally connected to the piston rod 101 of ahydraulic actuator 103. The cylinder of said actuator is pivoted at 105to the frame section 19.

The slotted link for the lower row of feed elements, as the parts aredepicted in Fig. 2, is also connected to the frame section 19 and disk95 by a second pair of links 91 and 93, and is also connected to saidframe section by a link 107 for parallel movement.

It is evident that if the disk 95 is rotated counterclockwise by theaction of the hydraulic actuator 103, as the parts are depicted in Figs.2 and 9, the upper slotted link 75 will shift its control link 71 to theleft, whereas the lower slotted link 75 will shift its control link 71to the right. This movement of the .control links will angularly shiftthe axes of rotation of the feed elements clockwise from the neutralpositions shown, andinsuch positions the feed elements will, uponrotation, feed a log forwardly from left to right. Since the controllinks will be moved equally in opposite directions, and since the upperlink is located below its row of feed elements (still referring to Fig.2), whereas the lower control link is located above its row of feedelements, the two opposed feed elements of each frame section will beadjusted the same angular extent in the same direction, so that theiraxes of rotation will remain parallel to one another and cooperate toevenly feedthe long along the machine.

It is pointed out that if the disk 95is turned by the actuator 103 in aclockwise ,direction, this aetionwill cause an opposite angulardisposition of thefeedelements,

6 which will result in feeding a log rearwardly, orfro n right to left.

The control box 93 forms part of a general control system provided inthe control booth, and is most clearly shown in Figs. 2, 7 and 8. Thecontrol box includesa square base plate 111 secured to a table or shelf113 forming part of the control booth. A sleeve 117 slidably extendsthrough the base plate 111 approximately centrally thereof and has theresponse-cable lever 89 fixed to the lower end thereof. Referring toFig. 8, a cable 118, connected to the lever 89, is trained about asheave 119 supported from the table 113 (see Figs. 8 and 9), the cable118 suspending from the free end thereof a weight 119a which at alltimes urges the lever $9 clockwise as the parts are depicted in Fig. 9.

Fixed to the base plate 111 is a circular guide plate 120 (Fig. 8)apertured to receive the sleeve 117 therethrough. Guided by the guideplate is a rotary, cylindrical housing member 121 engaging the outeredge of the guide plate and having secured to its upper edge a coverplate 123. The cover plate 123 has a lever arm 125 formed integrallytherewith and extending therefrom and by which the cover plate andhousing member 121 may be turned relative to the base plate 111.

The sleeve 117 protrudes through the cover plate 123 and has mounted onthe upper end thereof a set collar 127 by which the movable sleeve issupported on the cover plate 123. A lower set collar 129 is fixed to thesleeve 117 below the base plate 111, thus precluding endwise movement ofthe sleeve.

Supported by the guide plate lZl) is a circular switchsupporting plate1-51 apertured to receive the sleeve 117 therethrough, said supportingplate having a set collar 143 fixed concentrically thereto andadapted tobe adjustably secured to the sleeve 117 for purposes of initialadjustment of the mechanism, the sleeve 117 and the switch-supportingplate 141 being operable only by movement of the response-cable lever89. Mounted on the switch-supporting plate 141 are two normally openswitch units 145 and 147 (see Fig. 9) having electric currentcarryingcable pairs M8 and 149, respectively, extending therefrom and connectedto solenoids 150 and 151, respectively. These solenoids control thesupply to, and the release of, hydraulic fluid from thefeed-elementcontrol actuator 1193, previously mentioned, in a manner tobe presently described.

Each switch unit includes a horizontal arm 152 pivoted at 152a on aswitch-unit box 15%, said arm carrying a roller 153. The arms are biasedby springs (not shown) contained within boxes 1521; to normally hold therollers 153 in engagement with the ends of an arcuate cam 155 fixed tothe interior of the cylindricalhousing member 121. The arrangement issuch that when the rollers 153 are against the ends of the cam, theswitch units are in open condition, but when an arm is forced inwardly,as when its roller rides onto the innerperiphery of the cam, theassociated switch is closed.

The solenoids 151i and 151 are connected to a movable valve member 157of a hydraulic-fluid control valve 159, which is onlyschematicallyshown. Conduits 161 and 162 extend from the opposite ends of the valvecylinder tothc opposite ends of the actuator cylinder 103. A solenoid isoperable, when energized, to apply thrust to the valve member 157 andpush it toward the opposite end of the valve cylinder. An inlet conduit163 leads from the high-pressure side of a hydraulic-fluid pump 154 tothe center of the valve cylinder. An outlet conduit 165 extends from thecenter of the valve cylinder to the low-pressure side of the pump 164.

The valve member 157 has two inlet passages 156 and 167, the inlet endsof which are. spaced to provide a land facing and closing the conduit163 when the valve member is centrally positioned in the valvevcylinder. The inlet passages communicate. with the adjacent ends of thevalve cylinder. The valve member hasv two outlet a passages 168 and 169,the outlet ends of which are spaced to provide a land facing and closingthe outlet conduit 165 when the valve member is centrally positioned inthe valve cylinder. The outlet passages communicate at all times withthe remote ends of the valve cylinder.

The solenoids are of conventional construction and thus have been onlyschematically shown. Each has a built-in spring (not shown), said springfunctioning to urge the valve member to assume a position centrally ofthe valve cylinder.

The operation of the feed-element angle-control system is as follows.Fig. 9 shows the parts in neutral position with the feed elements 29rotating about axes parallel to the longitudinal axis of the machine.Assume that it is desired to feed a log forwardly, that is, from left toright in both Figs. 2 and 9. The lever arm is swung clockwise to causethe end of the earn 155, adjacent the roller 153 associated with theswitch unit 145, to force said roller to swing inwardly and close theassociated switch, while the end of the cam .155 adjacent the roller ofthe switch 147 retreats from said roller, which merely swings outwardlyinto engagement with the housing member 121, and thus the switch remainsopen. Closing of the switch energizes the solenoid 158 to force themovable valve member 157 to the left, as the parts are shown in Fig. 9,to bring the passage 166 into communication with the inlet conduit 163to supply hydraulic fluid under pressure to the right-hand end of theactuator cylinder 1G3, and to bring the passage 169 into communicationwith the outlet conduit to communicate the left-hand end of the actuatorcylinder 103 with the low-pressure side of the pump 164. The actuatorpiston is thus forced to the left, which acts through the disk 95, theslotted links 75 and the control links 71 to shift the axes of rotationof both rows of feed elements clockwise from the positions shown in fulllines in Fig. 6 to the dotted-line positions. In these positions, a logwill be fed forwardly through the machine.

Movement of the upper slotted link 75 to the left allows the weight 119aon the cable 118 to turn the lever 89 (and thus the plate 141 and theswitch units) clockwise only to such an extent that the roller for theswitch unit 145 rides off the inner periphery of the earn 155, and ontothe adjacent end of the cam, whereupon said switch opens and deenergizcsthe solenoid 150. When this occurs, the bulit-in springs for thesolenoids, before mentioned, force the valve member 157 back to itscentral position and thus cut off the supply of fluid to the actuator103, and also the discharge of fluid from said actuator. The fluidtrapped in the actuator 103 and the conduits 161 and 162, and within thevalve cylinder and movable valve member, holds the control links 71, andthus the feed elements 29, in their adjusted positions.

In order to determine the extent of angular adjustment of the feedelements 29, the cover plate 123 (see Fig. 7) is provided with anarcuate slot 171 Within which is disposed a fixed indicator 173 securedto the base plate 111. The indicator has a mark 175 adapted to cooperatewith marks 177 provided on the cover plate 123 adjacent the slot 171 toindicate the extent of angular adjustment of the feed elements 29,preferably in terms of the rate of longitudinal feed of the log.

Means to vary the lateral spacing of the rows of log-rotating elementsAs previously indicated, the feed elements 29 are adapted to be bodilyshifted inwardly and outwardly along the guides 23 to accommodatedifferent-sized, that is, diameter, logs. The two feed-elementassemblies of each frame section are connected for movement in unison.This arrangement will now be explained, and thereafter the manner ofcontrolling the bodily movement of the feed-element assemblies from thecontrol booth will be set forth.

Referring to Fig. 10, depending from each left-handfeed-element-supporting plate 25 is a pair of lugs 181, and dependingfrom each right-hand feed-element-supporting plate is a single lug 182,the lugs 181 being pivotally connected at 183 to a link 185, whereas thelug 182 is disposed between and pivotally connected at 187 to a doublelink 189. The link and double link 189 are pivotally connected togetherat 191.

Extending through all of the double links 189 of the opposed sets offeed elements intermediate the ends thereof is a common shaft 193 (seeFig. 1) which is preferably keyed to said links. There is a link 195 foreach double link, pivotally connected at one end to the common shaft 193and at its opposite end at 197 to the adjacent leg of the associatedframe section.

Referring to Figs. 1, 2, l0 and 11, a hydraulic actuator 201 is providedfor bodily shifting the sets of feed elements, said actuator including acylinder 203 pivoted at 205 to a tubular crosspiece 207, the lattermember being supported in part intermediate its ends by a pair ofangular brackets 209 (compare Figs. 1 and 10) fixed to the right-handside plate 22 of the frame section 15, as the parts are depicted in Fig.10. The cylinder 203 has therewithin a piston 210 (see Fig. 11) having apiston rod 211 extending from the cylinder and connected by a clevisconnection 213 (Fig. 10) to the plate 25 of the right-hand feed element29.

Cotmterbalancing each of the feed-element assemblies of the framesections 11 and 19, and the upper feedelement assemblies of the sections13- and 17, as the parts are depicted in Fig. 2, is a counterweight 221(see Figs. 2 and 3) which is suspended by a rope or cable 223, saidcable being trained over a sheave 225 and connected to the outer marginof the adjacent feed-clement-supporting plate 25 of the adjacent feedclement. Each sheave 225 is rotatably supported by a bracket 22.9 fromthe associated frame section.

Referring to Figs. l0 and ll, when the actuator 201 is actuated in amanner such as to force inwardly the feed-element assemblies of theright-hand row, the parts are depicted in Fig. 10, against theresistance of the weights 221, the links 189, 195 and 135. through thecommon shaft 193, force the feed-element assemblies of the opposite rowinwardly the same amount, the links being dimensioned to achieve thisresult.

The manner of controlling the spacing of the rows of the feed-elementassemblies will now be explained. Mounted on the frame section 15adjacent the actuator 201 (in a manner not shown) is a hydraulicfluid-control valve 232 (see Fig. ll), the construction of whichduplicates the valve 159 previously described, and hence simi- .larreference numerals have been applied to corresponding parts of the valve232. prime marks being added to the numerals to differentiate suchcorresponding parts. Conduits 233 and 234 connect the valve 232 to thecylinder of the actuator 201. Solenoids 235 and 236 control theoperation of the valve 232 and are in turn controlled through currentlines 243 and 244 by a control box 245 mounted on the table or shelf1.13 of the control booth.

Referring particularly to Figs. 12 through 16, the control box 245includes a housing having a horizontal face plate 249, an inclined faceplate 251, end plates 253, an angularly bent back plate 255, and a baseplate 257, the latter being secured to the shelf or table 113 of thecontrol booth. A control arrangement for the barkcutting-and-removinginstrumentalities to be described hereinafter is in part mounted beneaththe horizontal face plate 249, but of present concern is the controlarrangement for the actuator 201, which control arrangement is in partlocated beneath the inclined face plate 251.

The latter control arrangement includes a movable indicator carriage 261(see Fig. 14) slidably mounted by means of depending ears 263 on a pairof spaced, parallel facade-o2 rods 1265secured to the-endplates'j253.The carriage 261 is of generally open, rectangular configuration, .as isapparentfrom Fig. 15, and has mounted on .the left: side thereof, as theparts are depicted in Fig. 15, a handle 267 protruding through anelongated slot 269 (Fig. 12) formed in the inclined face plate 251. Thehandle 267 is adapted to have significance of position by virtue ofmarkings 271 provided on the face plate 251 adjacent the slot, themarkings being calibrated in terms of log size or diameter.

Mounted in spaced relation on the carriage 261 are two switch units 275and 277 having depending, pivotally mounted arms 279 and 281,respectively, carrying rollers 283 and 285, respectively (see Fig. 16).Operatively associated with the roller 283 .is a strip cam 287, andoperatively associated with the roller 285 is a strip cam 289,.said camsbeing laterally and longitudinally spaced with respect to one another,but being parallel to one another, and extending in opposite directionsfrom the rollers and presenting beveled ends to their respectivenollers.

The strip cams are mounted on a carriage 291 (-Fig. 14) slidablysupported by depending ears 292 on a pair of spaced parallel rods 293connected to the end' plates 253. The arms 279 and 281 are biased bysprings (not shown) to positions against stops (not shown) disposedWithin the boxes of the switch units. When the arms are against thestops the switches are open. The switch units are of conventionalconstruction, and therefore the detailed construction thereof need notbe shown. The current-supply lines 243 and 244, previously mentioned,are connected respectively to the switch units 275 and 277.

Connected to the right-handend of the carriage 291, as the parts aredepicted in Fig. 15, is a cable 301 which is trained over a sheave 303and suspends at its opposite end a-weight 305 (see the correspondingleft-hand end of the carriage 291 in Fig. 11).

Thus, the carriage 291 is constantly urged to the left, as the parts aredepicted in Figs. 2 and 11. Connected to the left-hand end of thecarriage 291, as the parts are depicted in Fig. 15, is one end of a,response cable 307, the cable then being trained over a sheave 309mounted on the control box, then extending through an opening in theshelf or table 113, and then being trained over a sheave;311 (see Fig.the latter sheavebeing mounted on the control booth. The other end ofthecable 307 is trained about a sheave 317 and isconnected at. 319 to thedouble link 189 associated with the framesection 15.

The operation of the control arrangement described above is as follows.For clarification, it will .bepointed out that in Figs. 2 and 11 thedirections are unavoidably opposite or contrary from those depicted inFigs. 12, 14, and 16. It may be assumed that the handle 1267 on thecontrol box 245 is moved to the right from'the position shown in Figs. 2and 11 (to the left as the parts are shown in Figs. 12, 14 and 15)toaccommodatexalog of larger size. This action causes theswitch-actuating roller 283 associated with the switchunit 275 to rideup and onto the associated strip 287 and pivots the arm 279 carrying theroller to close the switch incorporated in the switch unit 275 toenergize the solenoid 235 to supplyfluid under pressure to the inner endof the cylinder of the actuator 201. This forces the'two rows of feedelements to move in unison outwardly, such movement beingtransmittedthrough the double link 189' associated with the frame section 15,andcable 307 to the carriage 291 within the control box 245, thus movingthe carriage 291and strip 287 against the .pull of weights .305 andtoward the right, as the parts are depicted in Fig. 11, so as to bringthe beveled end of the strip 'cam"287 associated with the switch unit275 back under the associated switch-control roller 283. This actionopens the switch incorporated in the switch unit 275. and stopstheoperation of the actuator 201 by deenergizing the solenoid'235.Thesolenoids have built-in springs (not shown) which ill) function tobring. the movable waive element :of the v'alve 232 back to-itscentralposition wheneverthe solenoids are deenergized, this'action functioningto trap the hydraulic fluidin the'actuator 201 toholdthe rows of thefeed elements 29 in their adjusted position.

Movement of the handle 267 in the opposite direction, so as toaccommodate a log of smaller size, will cause hydraulic fluid, throughtheactuation of the switch in the switch unit 277 and the energizationof the solenoid 236, to be'supplied under pressure to the outer end ofthe cylinder of the actuator 201 and will release hydraulic fluid fromthe inner end of the cylinder of said actuator, the resultingapproaching movement of the two rows of feed elements tending to slackenthe cable 307. The response mechanism will then beoperable through thepull maintained by the weight 305 .on the cable 301 to slide thecarriage 291 tothe'lefttassuming the orientation of Figs. 2 and 11) tobring the beveled end of the strip cam 289 back under the .switch roller285 and thus open the switch unit 277.

In use, a series of live roll-s forming a conveyor will be employed tofeed logs into the machine, and a considerable advantage of providing anadjustable cradle lies in the fact that logs of'diiferent sizes may befed from a fixedlevel conveyor into the machine.

A review of the structure so far explained shows that each row of thefeed elements 29 is rotated in the same direction (in a counterclockwisedirection as the parts are depicted in Fig. 3) so as to rotate a logcradled thereby, and that provision is made for bodily shifting the rowsof feed elements inwardly or outwardly along inclined planes toaccommodate different-sized logs. Provision is also made forsimultaneously adjusting the angular positions of the axes of rotationof the feed elements from neutral positions either Way so as toselectively feed a log from left to right (as the par-ts are depictedinFig. l), which is the normal direction of travel, or to stop the logat any place along the machine, or to reverse the direction of feedingmovement of the log, and then to feed the log forwardly again, at theoption of the operator. Thus, the operator has full control over themovement of the log, and by stopping the log at a debarking station tobepresently described, or by reversing the direction of travel of thelog at the debarking station, a log of irregular or unusual shape orsize may be entirely debarked despite its shape.

Log hold-down units Operating in conjunetionwith the feedelements 29,are two hold-down units 331 and 333 mounted respectively on the framesections 13 and 17. Referring particularly to Figs. 1, 2, 3 and 18, eachhold-down unit includes a pair of bracket plates 33% fixed to theadjacent side plate 22 of the associated frame section. A horizontalshaft 337 is journaled in each pair of brackets adjacent the upper endthereof and has fixed thereto spaced arms 341, the lat ter carryingintermediate their lengths a pin 343. Pivotally connected at itsopposite ends to the pin 343 and a double lug 345 carried by theplate 25of the adjacent feed-element assembly is a link 347.

It follows from the abovestructure that when the rows of feed elementsare shifted inwardly or outwardly, the arms 341, through the links 347,are likewise shifted in a direction corresponding to the direction inwhich the feed elements are moved. That is, ifthe rows are shiftedapart, the arms are swung outwardly, and if the rows of feed elementsare moved toward one another, the arms 341 are swung inwardly. Thisaction adjusts the position of the hold-down units relative to the sizeof the log being processed.

The arms 341 have a shaft 349 journaled on their upper ends. A pair ofbell-crank members 353 are fixed intermediate their ends to the shaft349. The inner ends of thefbell-crank members have fastened thereto aplate 354 (compare Figs. 3 and .18), and pivotally carriedby said plateis a caster assembly including a hold-down roller 11 355 adapted toengage a log. The outer ends of the bellcrank members are curved towardone another (see Fig. 2) and journaled therein is a pin shaft 356 whichis connected to a piston rod 357 of a pneumatic actuator 359.

The caster assembly above mentioned includes a plate 360 swiveled by apivot 361 on the plate 354. The plate 360 carries downwardly curved arms362 rotatably supporting the hold-down roller 355. By this casterarrangement the hold-down roller will adjust itself to the helical pathof movement of the surface of the log which it engages, and thus notinterfere with forward movement or reverse movement of the log throughthe machine.

The actuator 359 has a cylinder 363 pivotally connected :at 364 to arms341 (compare Figs. 2 and 3). A counterwight arm 365, carrying acounterweight367, is fined to the shaft 337, previously mentioned.

In Figs. 2 and 3 the hold-down rollers 355 are shown engaging the loggenerally indicated at A, this position being caused by the supply ofair under pressure to the taneously, into yielding engagement with thetop of a log.

The supply of air under pressure to the pneumatic actuators 359 iscontrolled from the control booth in a manner to be indicatedhereinafter.

Arranged between the hold-down units 331 and 333 (consideredlongitudinally of the machine) are three pairs ofbark-and-cambium-layer-removing instrumentalities, the instrumentalitiesof each pair being disposed one on either side of the path of travel ofa log.

Swingahle bark-removing cutters The first set of bark-removinginstrumentalities or tools comprises two cutterhead units 381 and 383(see Figs. 2 and 17), the primary purpose of which is 'to remove bark.Each unit includes a swinging tubular arm 385 affixed adjacent its lowerend to a sleeve 336 journaled on a shaft 337, the latter being fixed toa pair of brackets 389 which in turn are fixed to the side plates 22 ofthe frame sections 13 and 15 (compare Figs. 1 and 17). At its oppositeend, each swinging arm 385 has fixed thereto in offset relation a clevismember 391 (see Fig. 19),

rotatably supporting a shift 393, the latter having fixedly securedthereto a rotary toothed-cutter 395. The teeth of the cutter are helicalas shown, the helix preferably being arranged so as to assist forwardfeeding movement of the log through the machine.

Each cutter 395 is adapted to be rotated in a counterclockwise direction(as the parts are depicted in Fig. 17) by a motor 401 mounted on thelower end of the assoeiated swinging arm and driving the cutter througha ehain-and-sprocket drive 403. The cutter is driven at a higher rate ofspeed than that of the feed elements 29, but in the same direction, sothat there is relative movement between the rotating cutters and the logto enable the cutters to perform their bark-removing operations withoutretarding the rotary movement imparted to the log by the feed elements29.

For urging the cutters into yielding engagement with a log, there isprovided a pneumatic actuator 465 for each cutterhead unit. A cylinder4417 of each actuator 405 is pivoted at 409 on the associated crossmember 207. A piston rod 41% of each actuator 405 is pivotally connectedby a clevis 410a to a lug 411 fastened to the associated swinging arm385 intermediate the length of said arm. The control of air underpressure to and from the pneumatic actuator 405 will be indicatedhereinafter along with 12 the description of the operation of otherbark-removing instrumentalities.

The right-hand cross member 297, as the parts are depicted in Fig. 24,is supported at its ends by a pair of plates 412 fixed to the outeredges of the two most adjacent plates 334 (compare Figs. 1, 2 and 3).The left-hand cross member 267 is supported at its ends by another pairof angle brackets 209.

Swingable and rockable bark-removing cutters T he second pair ofbark-and-cambium-layer-removing instrumentalities or tools, labeled 415and 416, is best shown in Figs. 2, 17, and 20 through 23. The twomechanisms are similar in construction and thus the construction of onlyone unit, unit 415, will be explained in detail. The unit 415 includes atubular support 417 having fixed adjacent its lower end a sleeve 418journaled on the shaft 387 (see Fig. 17). Fixed on the upper end of thesupport 417 is a forked member 419 (see Fig. 20) having a first pair offorked arms 420 and a second pair of forked arms 421, there being abearing sleeve 423 extending through and fixed to the four forked armsand protruding beyond the two outermost arms. Straddling the arms 420,and pivotally mounted on the sleeve 423, are depending arms 424 of aforked member having upwardly extending arms 425, and straddling thearms 421, and pivotally mounted on the sleeve 423, are depending arms426 of a forked member having upwardly extending arms 427. The twoforked members just mentioned are thus mounted for independent pivotalmovement. Rotatably mounted on the arms 425 by a shaft 428 is a cutter429 having helical teeth, and rotatably mounted on the arms 427 by ashaft 430 is a cutter 431 having helical teeth.

Each of the shafts 428 and 430 has reduced end portions (see Figs. 20and 22) rotatably received by the as sociated arms, and a clamp 433mounted on each outer associated arm fixes each shaft in any position towhich it has been rotatably adjusted, said clamp engaging a flange 434fixed to the outer end of each shaft. Formed on each of the shafts 428and 430 intermediate its ends is an eccentric portion 435 (see Fig. 22)on which is rotatably mounted the associated cutter. By rotatablyadjusting each of the shafts, the distance between the axis of rotationof the associated cutter and the axis of sleeve 423 may be varied for apurpose to presently appear.

Up to this point, it is apparent that, if the tubular support 417 wereswung inwardly toward a log, the two cutters would merely pivotrearwardly about the sleeve 423, and hence no forcible engagement of thecutters and the log could be achieved.

However, there is provided an equalizing bar 439 (see particulary Fig.23) having its ends loosely received through apertures 44% (see Fig. 21)formed in a pair of rearwardly extending lugs 440 fixed to the outercuttersupporting fork arms. Heavy cotter pins 441 are provided on theends of the equalizing bar. Formed centrally in the bar 439 is anopening 439a (Fig. 23) through which loosely extends the upper end of apivot element 442 fixed at its lower end to the support 417 (see Fig.21). The upper end of the element 442 has a heavy cotter pin 443provided thereon. The opening 439a in bar 439 is sufficient to allow theequalizing bar not only to pivot in its own plane but also to wobble orrock when the cutters pivot back and forth on the sleeve 423.

It is evident from the above description that the cutters areself-adjusting and that one cutter may ride upon a knot or branch stub,such motion being transmitted through the equalizing bar 439 to theother cutter to thrust it inwardly into engagement with the side of theknot or branch stub, or the area immediately surrounding the extendingthrough and .being joumaled in the sleeve 423. Also fixed to theshaft457 are sprockets-459 and .461, which drive respectivelysprcckets 463.and 465 through chains 467 and 469, respectively, the latter-namedsprockets being respectively rotatably mounted on the eccentric portionsof the shafts 428 and 430. The sprockets 463 and 465 are fixed to thecutters 429 and 431, respectively. The cutters are thus driven inthesame direction at the same speed.

To obtain the correct tension in the chains 467 and 469, the shafts 428and 430 may be rota-tably adjusted upon loosening the clamps 433 to varythe distances between the axes of the upper and lower pairs ofsprockets, as the parts are shown in Fig. 20.

For swinging the cutters inwardly and outwardly with respect to a logsupported by the feed elements 29, there is provided a pneumaticactuator 471 for each tubular support 417. The outer end of the actuatorcylinder is pivotally mounted at 473 to the crosspiece 207 (see Fig.17), and the actuator piston rod 475 is pivotally connected at 477 tothe support 417 at a place between the shaft 387 and the cutters. Themanner of supplying air to and discharging air from the actuator will beindicated hereinafter.

Swingable bark-removing brushes The third pair ofbark-and-cambium-layer-removing instrumentalities is best shown in Figs.24 to 27. The primary purpose of the third set of instrumentalities isto remove the cambium layer or inner bark on a log, especially aroundand on a knot, branch stub, and the like; and the secondary purpose ofthe third set of instrumentalities is to remove any minor portions ofbark on the log which have not been previously removed.

As is apparent in Figs. 2 and 24, each of the third pair ofinstrumentalities comprises a brush unit, one brush unit being indicatedat 481 and the other brush unit be ing indicated at 483. Each brush unitcomprises a swinging arm 4855 having an offset lower portion journaledby a sleeve 486 on a shaft 437 fixed to a pair of brackets 489 fixed tothe side plates 22 (see Fig. 1) on the adjacent legs of the framesections and 17. Rotatably carried by the upper end of each arm 485 is ashaft 495 having fixed to the inner end thereof a wire brush 497. Fixedto the outer end of each shaft is'a sprocket 499, and driving thesprocket is a chain '501 driven bysprocket 503 fixed to the shaft of amotor 595, the latter being mounted on the lower end of the-arm 485.

Referring particularly to Figs. 25 and 26, each wire brush comprises abase plate 511 having aplurality of still, short, heavy cable sections513 welded in sockets or r holes provided in said plate. As is apparentfrom Fig. 26, cable sections are not'provided on the central portion ofthe plate, leaving a cavity or recess in the center of the brush. Thiscavity or recess is very important to the operation of the brushes, asit allows them to fit over and generally conform to the configuration ofa knot or branch stub and thus remove the bark and cambium layer on thesides and in the area surrounding the knot or stub, these places beingmost dilficult areas from which to remove bark and cambium layer.

For holding the wire brushes in engagement with the exterior of a logbeing. debarked, there is provided a pneumatic actuator 521 foreachwire-brush unit, the cylinder of each pneumatic actuator being pivotedat 523' to the associated cross member 207. The piston rod 525 of eachpneumaticactuator is pivotally connected at 527 to the arm 485intermediate the length thereof.

Hydraulic control for the pneumatically positioned cutters and brushesThe-pneumatic actuators for the first, second, and thirdbark-and-cambium-layer-removing instrumentalities are adaptedto beindependently supplied with air underpressure in a substantiallyduplicate mannerto cause the associated bark-and-cambium-layer-removingdevices to yielding-1y but forcibly engage; a log, by selectiveoperation of a plurality of control handlesprovided on the-control box245. For convenience in description, the control handles have been giventhe same reference numerals as the instrumentalities which they control,the subscript a being added to distinguish between the parts (compareFigs.,2.and 12).

Referring particularly to Fig. 27, where the control arrangementfor thewire-brush assembly 483 is disclosed, a description of the manner andoperation of this control system will serve to indicate how the otherinstrumentalities, as well as the two hold-down devices 331 and 333, areoperated.

A control handle 483a has fixed to its lower end a cam 535 pivotallymounted on a pivot rod 537 (see Figs. 12 and 13) fastened in the endplates 253 of the control box 245. There is a lever 539 pivoted on apivot rod 541 secured at its ends in the end plates of the housing, oneend of the lever resting on the cam 535 and the other end resting on theprotrudingportion of a valve member 545 formingpart of a valve 547 fixedto the base 257 of the housing. A hydraulic fluid-supply line 555 (seeFig. 27) communicates with the lower end of the chamber of the valvebody of the valve 547, and a hydraulic fluid-dischargeconduit 551communicates with the upper end of said chamber. A supply-and-dischargeconduit 559 communicates at one end centrally with the valve chamber,and then branches to provide branch conduits 563 and 565 communicatingwith valve 567 and 569, respectively, which valves are of conventionalconstruction. A compression spring 549, arranged within the valve 547,constantly urges the valve member 545 upwardly and therefore pivots thelever. 539 in a direction to constantly dispose it inengagement with,the cam 535.

The valve 567 has a movable valve member 571 biased upwardly by a spring573, and the valve 569 has a movable valve member 575 constantly biasedupwardly by a spring 577. It is apparent that the branch conduits 563and 565 communicate respectively with the upper ends of the bores withinwhich the valve members 571 and 575 travel. Suitable stops or lugs ineach of the valves 567 and 569 limit upward movement of the respectivevalve members. ,Also, suitable stops are provided for limiting downwardtravel ofthe valve members.

It is evident that when hydraulic fluid is supplied through conduits,559, 563 and 565, the two valve members 571 and 575 are both forceddownwardly simultaneously. In order to supply, hydraulic fluid to theconduits 563 and 565, the valve member 545 is provided with a passage581 having an enlarged right-hand portion, as the parts are depicted inFig. 27, which is in constant communication with the conduit 559, andhaving an upper passageportion communicating with the conduit 551 whenthe valve member is in its upper position, but being cut off fromcommunication with said conduit when said valve member is depressed. Thepassage 581 also has a lower leg portion which is normally out ofcommunication with the conduit 555 but is adapted to communicate withsaid conduit when the valve member 545 is depressed.

Assuming that the control member 483a is in its upright position, it isapparent that the valve member 545 will be disposed in its upwardposition, and thus the conduit 559 is in communication with thedischarge conduit 551, and'thus no pressure is applied to the valvemembers 571 and 575, andtherefore they remain in their upward positionsunder the influence of the springs 5'73 and 577, respectively. However,the control member 483:: is adapted to be swung counterclockwise, as theparts are depicted in Fig. 13, to the broken-line position, which actionthrough the cam 535 and the lever 539 depresses the valve member 545 andplaces the conduit 559 in com munication with the supply conduit 555 sothat hydraulic fluid is simultaneously supplied to the upper ends of thevalve members 571 and 575, depressing said valve memhers. The effect offorcing the just-mentioned valve memhers downwardly will now beexplained.

Air under pressure from a source (not shown) is adapted to be suppliedto the valves 567 and 569 through the supply conduits 585 and 587,respectively. As shown in Fig. 27, the conduit 587 normally communicateswith a conduit 591 through a passage 593 formed in the valve member 575,Whereas the conduit 585 is normally out of communication with a conduit595, but is adapted to be brought into communication with the conduit595 by a passage 597 formed in the valve member 571 when the valvemember is forced downwardly. The conduit 591 communicates with theright-hand end of the cylinder for the actuator 521, whereas the conduit595 communicates with the left-hand end of said cylinder. Formed in thevalve member 571 is an exhaust passage S99 normally communicating theconduit 595 with the atmosphere through the lower end of the bore withinwhich the valve member 57]. travels. T he conduit 591 is adapted to beplaced in communication with a discharge or exhaust conduit 601 by apassage 603 formed in the valve member 575 when the valve member isdepressed.

The operation of the control system for wire-brush unit 483 is asfollows. When the machine is entirely at rest and when there is nosupply of air under pressure to the valves 567 and 569, the wire-brushunit swings under the influence of gravity clockwise from the positionshown in Fig. 27 toward the zone to be occupied by the log. When the aircompressor for the system is energized and air is supplied to the valves567 and 569, air under pressure traveling through the conduit 587,passage 593 and conduit 591 into the actuator will force the wire-brushunit 483 to swing counterclockwise out of the zone to be occupied by thelogs. However, when at an appropriate time it is desired to bring thewire brush into forcible but yielding engagement with the log, thecontrol handle 483a is swung counterclockwise to communicate the conduit591 with the atmosphere and to communicate the conduit 595 with thesupply of air under pressure so that the wire-brush unit is forcedclockwise to bring the brush 497 into engagement with the log.

By locating the control handles in the arrangement shown in Fig. 12, itis apparent that the operator may with one hand grasp two adjacentcontrol handles and pull them forwardly. The control handles arearranged so that the two wire-brush handles are next to one another, sothat handles of the first two bark-removing instrumentalities are nextto one another, and so that the handles of the second pair ofbark-removing instrumentalities are next to one another. Normally, theoperator will desire to bring each pair of bark-removinginstrumentalities into substantially simultaneous engage ment with alog, and this he may readily accomplish by pulling forward theappropriate adjacent pair of handles.

Summary of operation The operation of the machine has been explainedalong with the .escription of the various assemblies and mechanisms andtherefore need not be repeated in detail. However, in general, theoperator will be apprised of, or will visually estimate, the size of thelog to be debarked, and will shift the control handle 267 (Fig. ll) oneway or the other to vary the size of. the cradle such as to enable thelog to move into the cradle from a fixed-levelsupply arrangement, andalso to provide a cradle to properly suport the log. As the forward endof the log is fed into the machine, the operator will swing the controlhandle 125 clockwise (Fig. 9) to adjust the angular positions of theaxes of rotation of the feed elements to feed the log forwardly fromleft to right as the parts are depicted in Fig. 2. As the forward end.of the log reaches the hold-down unit 331, the operator will, normally,pull forwardly on the control handle 331a to bring the associatedhold-down roller into engagement with the log.

The hold-down roller, being caster mounted, will automatically adjustitself to the helix angle of the strip of log surface passingtherebeneath so as not to interfere with the forward feed of the log andyet yieldably but forcibly retain the log on the cradle. As the forwardend of the log reaches the first pair of bark-cutting instrumentalities,the operator will pull forwardly on the control handles for thesecutting instrumentalities to bring them into engagement with the surfaceof the log. The cutting heads of these units are arranged to rotate inthe same direction as that of the logs, but at a higher rate ofperipheral speed, and thus do not interfere with the retative movementimparted to the log by the feed elements, and yet have relative movementto the log surface, and thus cut, tear and mutilate the bark surface,and also to some extent remove the underlying cambium layer. Because thebark-cutting-and-removing instrumentalities are all yieldably forcedinto engagement with the log, they will oscillate back and forth so asto accommodate irregularities in the contour of the log.

When the forward end of the log reaches the second pair ofbark-cutting-and-removing instrumentalities 415 and 416, the operatorwill grasp the adjacent pair of control handles 415a and 416a and bringthe cutting heads of the units 415 and 416 into forcible but yieldingengagement with the surface of the log. These cutting heads will furthercut, tear and mutilate the bark and further remove portions of thecambium layer. The second pair of bark-cutting-and-removinginstrumentalities, being self-adjusting to the contour of knots, branchstubs and the like, will account in a considerable degree for theremoval of back and portions of the cambium layer around these knots,branch stubs, and other irregularities including recesses in the logs.

As the forward end of the log reaches the wire-brush units, the operatorwill grasp the adjacent handles 481a and 483a and pull them forwardly tobring the wire brushes into yielding but forcible engagement with thesurface of the log, which has now been substantially depleted or clearedof bark, although some portions of bark will remain. The wire-brushunits will remove these minor portions of the bark and the cambiumlayer. As knots, branch stubs and the like are brought into the regionof activity of the wire-brush units, the wire-brush units will fit overthese knots, branch stubs and the like and completely remove thebark andcambium layer on and around such portions.

The operator will observe the progress of the log through the machineand, whenever he sees that a particular spot has not been cleared ofbark and cambium layer, he may bring the control handle 125 to a neutralposition to allow the various instrumentalities to operate on theuncleared portion, or may reverse the handle 125 to move the log fromright to left, or rearwardly, so as to allow thebark-cutting-and-removing instrumentalities to have a second pass at theuncleared region. Many of the logs to be debarked will be successfullyand entirely debarked both of bark and cambium layers on the first passthrough the machine. However, one primary advantage of the presentmachine is that it may entirely remove the bark and underlying cambiumlayer from all sizes and types and configurations of logs in variousconditions, such as logs which are entirely green to those which havebeen allowed to dry so that the bark and the cambium layer are verydifficult to remove in the usual machine. When a particularly difficultlog is encountered, the operator, because of the versatility of thepresent machine, may subject the particular difficult area to a thoroughcleaning operation by holding it stationary at a bark-removing station,or by reversing the feed of the log and subjecting the particular regionto several passes by particular sets of bark-removing instrumentalities.

It is pointed out that by making the peripheral speed of the cutterheadsgreater than that of the log, the cutterheads assist in maintaining,rather than retarding, rotation f a 102 a d also a s the bar t be cut no smal er Pieces than would be. t e a e e e the per phe a pe d slowerthan that of the log. This is so. because at a slower speed thecutterheads would exert a hoeing action on the bark and thus the size ofthe pieces of bark removed would depend on the strength of the bondbetween the bark and the cambium layer rather than on the spacing andspeed of the cutterhead teeth. By cutting the bark into smaller pieces,the bark is ready for use as fuel without being run through a hoggingmachine.

A further advantage of the cutterheads is that the helix angle of thecutters is arranged to assist longitudinal movement of a log through themachine. That is, the teeth cut along a diagonal path generally parallelto the spiral path of the bark traveling thereunderneath, rather thanacross such path. Thus the cutting action is like that of a scytherather than that of a hoe-type pull and enables the bark to be removedwithout excessive tearing which would damage the useful wood fibers ofthe log. The provision of helical cutting teeth also prevents cloggingof the heads with bark, because as bark accumulates in the groovesbetween the teeth, subsequent pressure by engaged bark creates forcesacting on the accumulating bark urging it along the grooves and out theends thereof.

The symmetrical disposition of the barking tools and brushes relative tothe log and their engagement with the log at places above the centralaxis of the log tends to maintain the log on its cradle and alsoprevents the log from camming itself under a tool or brush and Oil ofthe cradle. Also, the working faces of the brushes are wider than thetools so that the brushes sweep across the entire spiral working pathsof the tools to effectively remove loose bark and also cambium layerportions,

The advantages of the present machine have been indicated heretofore,but it is believed important to poipt out that it is the capability ofthe machine of the present invention for handling all types and kinds oflogs which accounts for its success.

Having described the invention in what is considered to be a preferredembodiment thereof, it is desired that it be understood that thespecific details shown are illustrative and that the invention may becarried out in other ways within the scope of the appended claims.

I claim:

1. In a log-barking machine, log-supporting means for feeding a loglongitudinally along a predetermined path, and rotary wire-brush meansarranged adjacent said supporting means for engagement with a logsupported by said supporting means, said wire-brush means having thebark-engaging portions thereof arranged for rotation in a plane parallelto the path of travel of such log and being formed with a recess toenable the wire-brush means to conform generally to the contour of aknot or stub on a log and remove any bark and cambium layer locatedthereon and therearound, the axis of rotation of the rotary wire-brushmeans extending through a log supported by the log-supporting meanswhereby the recessed portion of the rotary wire-brush means may surrounda knot or stub on such log.

2. In a log-barking machine, means for rotating a log, means arrangedadjacent said rotating means operable to remove bark from such log, andincluding a pair of rotary toothed cutters, means mounting the cuttersfor bodily movement relative to one another and for movement toward andaway from such log, and means for imparting the movement of one cuttertoward and away from such log oppositely to the other cutter whereby,when one cutter rides upon a knot or stub, the other cutter is thrustinwardly to engage such log in the area surrounding such knot or stub toremove bark-andcambium-layer material therefrom.

3. In a log-barking machine, means for supporting and rotating a logabout its longitudinal axis, a self-adjusting cutter device for removingbark from such log, said device including a pair of cutters mounted forbodily movement relative to one another and, for swinging movementtoward and away from such log supported by said means, and an equalizingbar articulately connected at its ends to the cutters and pivotallymounted intermediate its ends whereby movement of one cutter will beimparted oppositely to the other.

4. A log-barking machine including means for supporting a log to bedebarked and feeding a log longtiudinally along a predetermined path oftravel, toothed barkremoving means arranged adjacent the supportingmeans and engageable with a log supported by said supporting means forremoving at least a portion of itsbark and exposing and removing part ofits underlying cambium layer, and wire-brush means arranged adjacentsaid supporting means beyond said toothed bark-removing means, in thedirection of travel of such log, and engageable with such log forremoving any unremoved bark portions and cambium layer, said rotaryWire-brush means being formed with a concavity to enable it to fit ontoa knot or stub on a log so as to remove any bark and cambium layerlocated on and surrounding such knot or stub, said toothed bark-removingmeans including a pair of rotary toothed cutters, each being mounted formovement toward and away from a log, and means for imparting themovement of one cutter toward and away from a log oppositely to theother cutter whereby, when one cutter rides upon a knot or stub, theother cutter is thrust inwardly to engage such log in an areasurrounding such knot or stub to remove bark-and-cambium-layer materialtherefrom. I

5. In a log-barking machine, a rotary, toothed barking tool, meanssupporting said tool, a rotary wire brush having the bristles thereofextending generally parallel to an axis of rotation of the brush, meansfor supporting said brush adjacent said barking tool, means forsupporting a log adjacent said toothed barking tool and said wire brushwith a longitudinal axis of such log extendns Par l l to th xis o t ti oaid toothed barking ol and 9. o the ax s rotat o of sai r ush, and means-d ue dent y iedin l u in sai ba kis to l a d a d W re b ush to ard sa de Sa d th n t ol hav n a plu ali of indepe den sepa ate. i umerent allyspa ed ba king et a Jo's-ba kin maeh ne a a kin ool s r a P of rotarylog-barking tool mean m un in the ools 9 s id support for relativebodily swin i g o ment a out a common ax insane n a 1 .t -z.' sa d oo sw th ai support and b n pe able P si e to cause the swin in more ment oon ool abo a d axis to be ransmi sdopnosi qly t the oth ol means forsupporting a log adjacent said barking tools, and means for forcing saidtools toward such log.

7. In a log-barking machine, a barking-tool support, a pair of rotarylog-barking tools, means mounting the tools on said support for relativebodily swinging movement about a common axis, means interconnecting saidtools with said support and being operable positively to cause theswinging movement of one tool about said axis to be transmittedoppositely to the other tool, means for supporting a log adjacent saidbarking tools, means for forcing said tools toward such log, and powermeans for driving said tools including elements mounted for rotationabout said axis and being drivingly connected with said tools.

8. In a log-barking machine, a barking-tool support, a pair of rotarylog-barking tools, means mounting the tools on said support for relativebodily swinging movement about a common axis, means interconnecting saidtools with said support and being operable positively to cause theswinging movement of one tool about said axis to be transmittedoppositely to the other tool, means for supporting a log adjacent saidbarking tools, means for forcing said tools toward such log, saidbarking tools having teeth therearound, said log-supporting meanssupporting such log with its longitudinal axis extending

